This completes 9fdd41e8.

fix wraparound logic, add tests to fail cases and comments to clarify conventions of fundamental domains

apply position transformation before determining dimensionality;
this allows 2D projections of 3D systems to be plotted.

See merge request !161

This reverts commit 1e6c0860, reversing
changes made to 2c5da944.

The changes to Kwant's Lapack wrappers depend on features from
Scipy 0.16, so it cannot be merged into stable branch, which
depends on Scipy 0.14.

fix pickling on Cython 0.26

See merge request !175

Closes #170

enable PDF documentation builds

See merge request !171

Produce vector graphics, rather than rasterizing,
as rsvg-convert does.

Add the 'unicode-math' package and set the
latex engine to 'xelatex'.

Closes #126.

improve 'attach_lead' docstring

See merge request !170

sympy is installed in the Kwant testing image now.

We can now use Scipy's Cython interface to Lapack, which removes the need for us to explicitly link against blas or lapack ourselves. Also cut down boilerplate by re-arrange the existing Lapack wrappers to use Cython fused types.

Closes #28

See merge request !149

We use Cython's import mechanism to use the the same lapack used
by Scipy, so we no longer need to explicitly link against lapack
or blas.

Closes #166.

There is no point in repeating the docstring in 2 places, though we
leave in the explanation of what this means in the "simplest case", i.e.
lowest modes first, for clarity.

Previously a point defect introduced by an incorrect treatment
of the origin produced erroneous scattering. We also update the text
to reflect the actual magnetic potential used.

Closes #156.

I assume that most people encounter the tutorial example scripts by
reading the documentation, and not by viewing the tutorial subdirectory
of a checked-out Kwant source.

That's the motivation for moving all the manipulations of tutorial
scripts from setup.py to doc/Makefile.  Previously, a successful 'make
html' would require a preceding execution of 'setup.py build_tut'.  Now,
a simple 'make html' is enough.

While at it, I reorganized where the example scripts and their outputs
are stored.  Everything is now in 'doc/source/code' with its three
subdirectories 'download' (to be shown to readers), 'include' (with
include markers), and 'figure' (figure generation & figures).  This
organization is clearer and also makes the generation of figures
separate from the tutorial.